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IdentificationPharmacologyInteractionsReferencesTrialsEconomicsPropertiesSpectraTaxonomyDiphenhydramine
Identification
- Name
- Diphenhydramine
- Accession Number
- DB01075 (APRD00587, DB06975)
- Type
- Small Molecule
- Groups
- Approved, Investigational
- Description
Diphenhydramine, also known commercially as Benadryl, is a first generation antihistamine that is used primarily for the treatment of seasonal allergies. However, it also has antiemetic, antitussive, hypnotic, and antiparkinson properties. As histamine receptors exist both peripherally and in the central nervous system, diphenhydramine has been shown to cause sedation due to its competitive antagonism of histamine H1 receptors within the central nervous system. While its use in in allergies has largely fallen out of favour due to this sedative effect, diphenhydramine has been repurposed for use within many OTC (over the counter) cough-and-cold medications that have been marketed for "night time" use.
Diphenhydramine is also used in combination with 8-chlorotheophylline as the anti-nausea drug Dimenhydrinate where it is utilized primarily for its antagonism of H1 histamine receptors within the vestibular system [4].
Diphenhydramine has also been shown to be implicated in a number of neurotransmitter systems that affect behaviour including dopamine, norepinephrine, serotonin, acetylcholine, and opioid [3]. As a result, diphenhydramine is being investigated for its anxiolytic and anti-depressant properties.
- Structure
Structure for Diphenhydramine (DB01075)
- Synonyms
- 2-(Benzhydryloxy)-N,N-dimethylethylamine
- 2-diphenylmethoxy-N,N-demthylethanamine
- alpha-(2-Dimethylaminoethoxy)diphenylmethane
- beta-Dimethylaminoethanol diphenylmethyl ether
- beta-Dimethylaminoethyl benzhydryl ether
- Difenhidramina
- Diphenhydraminum
- N-(2-(Diphenylmethoxy)ethyl)-N,N-dimethylamine
- O-benzhydryldimethylaminoethanol
- β-dimethylaminoethyl benzhydryl ether
- Product Ingredients
Ingredient UNII CAS InChI Key Diphenhydramine citrate 4OD433S209 88637-37-0 SPCKHVPPRJWQRZ-UHFFFAOYSA-N Diphenhydramine hydrochloride TC2D6JAD40 147-24-0 PCHPORCSPXIHLZ-UHFFFAOYSA-N Diphenhydramine methylbromide UJO67AO8YI 31065-89-1 BDQPXVWYFLTETB-UHFFFAOYSA-M Diphenhydramine salicylate 707L3YC54L 7491-10-3 RTSZUSOHOIFYSY-UHFFFAOYSA-N - Active Moieties
Name Kind UNII CAS InChI Key Phenol unknown 339NCG44TV 108-95-2 ISWSIDIOOBJBQZ-UHFFFAOYSA-N - Product Images
- Prescription Products
Name Dosage Strength Route Labeller Marketing Start Marketing End Benadryl Injection, solution 50 mg/1mL Intramuscular; Intravenous Parke Davis Div Of Pfizer Inc 1957-12-30 2007-01-31 US 
Benadryl Injection, solution 50 mg/1mL Intramuscular; Intravenous Parke Davis Div Of Pfizer Inc 1947-03-06 2008-01-31 US Benadryl Inj. 50mg/ml Liquid 50 mg Intramuscular; Intravenous Warner Lambert Canada Inc. 1994-12-31 2000-11-27 Canada 
Diphenhydramine HCl Inj USP 50mg/ml Liquid 50 mg Intravenous International Medication Systems, Limited 1974-12-31 1997-08-15 Canada Diphenhydramine HCl Injection, USP Solution 50 mg Intramuscular; Intravenous Sterimax Inc 1994-12-31 Not applicable Canada Diphenhydramine Hydrochloride Injection Solution 50 mg Intramuscular; Intravenous Fresenius Kabi 2012-02-17 Not applicable Canada Diphenhydramine Hydrochloride Injection USP Liquid 50 mg Intramuscular; Intravenous Sandoz Canada Incorporated 1983-12-31 Not applicable Canada Diphenist 50mg/ml Liquid 50 mg Intramuscular; Intravenous Omega Laboratories Ltd 1997-10-28 Not applicable Canada Scheinpharm Diphenhydramine Inj.50mg/ml Solution 50 mg Intramuscular; Intravenous Schein Pharmaceutical Canada Inc. 1996-09-30 2004-07-26 Canada - Generic Prescription Products
Name Dosage Strength Route Labeller Marketing Start Marketing End Diphendydramine Hydrochloride Capsule 25 mg/1 Oral Remedy Repack 2010-12-17 2017-04-24 US 
Diphenhydramine Injection, solution 50 mg/1mL Intravenous Remedy Repack 2013-11-18 2017-01-20 US Diphenhydramine Injection, solution 50 mg/1mL Intramuscular; Intravenous Fresenius Kabi 2002-08-01 Not applicable US Diphenhydramine Hydrochloride Capsule 50 mg/1 Oral State of Florida DOH Central Pharmacy 2009-07-01 Not applicable US 
Diphenhydramine Hydrochloride Injection, solution 50 mg/1mL Intramuscular; Intravenous Fresenius Kabi 2013-03-26 Not applicable US Diphenhydramine Hydrochloride Capsule 50 mg/1 Oral Remedy Repack 2013-03-25 2014-03-25 US Diphenhydramine Hydrochloride Capsule 50 mg/1 Oral Mylan Institutional 2011-08-23 2013-12-31 US Diphenhydramine Hydrochloride Injection 50 mg/1mL Intramuscular; Intravenous Nucare Pharmaceuticals,inc. 1972-11-27 Not applicable US Diphenhydramine Hydrochloride Injection, solution 50 mg/1mL Intramuscular; Intravenous Mylan Institutional LLC 2013-05-09 Not applicable US Diphenhydramine Hydrochloride Injection, solution 50 mg/1mL Intramuscular; Intravenous General Injectables & Vaccines 2017-06-13 Not applicable US - Over the Counter Products
Name Dosage Strength Route Labeller Marketing Start Marketing End 7 Select Allergy Tablet 25 mg/1 Oral 7 Eleven 2014-04-22 Not applicable US 7 Select Allergy Childrens Solution 12.5 mg/5mL Oral 7 Eleven 2014-08-05 Not applicable US 7 Select Night Time Sleep Aid Solution 50 mg/30mL Oral 7 Eleven 2014-04-22 Not applicable US Adult Allergy Solution 50 mg/20mL Oral Chain Drug Consortium 2015-05-04 Not applicable US Adult Allergy Relief Solution 50 mg/20mL Oral Walmart Stores 2017-05-03 Not applicable US After Bite Outdoor Gel 20 mg/1mL Topical Tender Corporation 2016-11-01 2018-03-01 US After Bite Outdoor Gel 20 mg/1g Topical Tender Corporation 2018-03-01 Not applicable US After Bite Plus Gel 20 mg/1g Topical Tender Corporation 2018-03-01 Not applicable US After Bite Plus Cream 20 mg/1mL Topical Tender Corporation 2012-07-03 2018-03-06 US After Bite Xtra Gel 20 mg/1g Topical Tender Corporation 2018-03-01 Not applicable US - Mixture Products
Name Ingredients Dosage Route Labeller Marketing Start Marketing End 7 Select Ibuprofen PM Diphenhydramine citrate (38 mg/1) + Ibuprofen (200 mg/1) Tablet, film coated Oral 7 Eleven 2014-08-05 Not applicable US 7 Select Night Time Severe Cold Cough and Flu Diphenhydramine hydrochloride (25 mg/1) + Acetaminophen (650 mg/1) + Phenylephrine hydrochloride (10 mg/1) Powder, for solution Oral 7 Eleven 2016-01-25 Not applicable US 7 Select Night Time severe cold, cough and flu Diphenhydramine hydrochloride (25 mg/1) + Acetaminophen (650 mg/1) + Phenylephrine hydrochloride (10 mg/1) Powder, for solution Oral 7 Eleven 2015-11-12 2017-08-01 US 7 Select Pain Relief PM Diphenhydramine hydrochloride (25 mg/1) + Acetaminophen (500 mg/1) Tablet, film coated Oral 7 Eleven 2014-09-04 2016-07-22 US 7-Select Advil PM Diphenhydramine citrate (38 mg/1) + Ibuprofen (200 mg/1) Tablet, coated Oral Lil' Drug Store Products, Inc. 2011-06-01 2017-12-31 US Aceta-gesic Diphenhydramine hydrochloride (12.5 mg/1) + Acetaminophen (325 mg/1) Tablet, coated Oral Remedy Repack 2014-08-08 Not applicable US Aceta-gesic Diphenhydramine hydrochloride (12.5 mg/1) + Acetaminophen (325 mg/1) Tablet, coated Oral Rugby 2014-06-30 Not applicable US Acetadryl Diphenhydramine hydrochloride (25 mg/1) + Acetaminophen (500 mg/1) Tablet, film coated Oral Aidarex Pharmaceuticals LLC 2011-07-21 Not applicable US Acetadryl Diphenhydramine hydrochloride (25 mg/1) + Acetaminophen (500 mg/1) Tablet, film coated Oral Physicians Science & Nature Inc. 2011-07-21 2016-05-31 US Acetaminophen / Diphenhydramine 500/25 mg Diphenhydramine hydrochloride (25 mg/1) + Acetaminophen (500 mg/1) Tablet Oral Reliable 1 Laboratories 2015-11-01 Not applicable US - Unapproved/Other Products
Name Ingredients Dosage Route Labeller Marketing Start Marketing End Airacof Diphenhydramine hydrochloride (12.5 mg/5mL) + Codeine phosphate hemihydrate (7.5 mg/5mL) + Phenylephrine hydrochloride (7.5 mg/5mL) Liquid Oral Centurion Labs 2010-01-08 2016-05-02 US Benadryl Diphenhydramine hydrochloride (50 mg/1mL) Injection, solution Intramuscular; Intravenous Physicians Total Care, Inc. 2006-01-13 2010-12-29 US Benadryl Diphenhydramine hydrochloride (50 mg/1mL) Injection, solution Intramuscular; Intravenous Physicians Total Care, Inc. 1994-06-01 2010-12-29 US Contrast Allergy PreMed Pack Diphenhydramine hydrochloride (50 mg/50mg) + Prednisone (50 mg/50mg) Kit Shertech Laboratories, Llc 2016-09-13 Not applicable US Dicopanol Diphenhydramine hydrochloride (0.86 g/0.86g) Kit Oral California Pharmaceuticals, Llc 2016-01-01 Not applicable US Dicopanol Diphenhydramine hydrochloride (0.75 g/0.75g) Kit Oral Fusion Pharmaceuticals LLC 2010-02-08 Not applicable US DiphenMax Diphenhydramine (25 mg/1) + Phenylephrine (10 mg/1) Tablet, chewable Oral River's Edge Pharmaceuticals, LLC 2008-01-01 2009-11-09 US Endal CD Diphenhydramine hydrochloride (10 mg/5mL) + Codeine phosphate hemihydrate (7.5 mg/5mL) + Phenylephrine hydrochloride (7.5 mg/5mL) Syrup Oral Tiber Laboratories 2009-12-09 2009-12-31 US FIRST BXN Mouthwash Diphenhydramine hydrochloride (0.84 mg/1mL) + Lidocaine hydrochloride (6.75 mg/1mL) + Nystatin (6.75 mg/1mL) Kit Oral CutisPharma, Inc 2009-09-08 Not applicable US FIRST Dukes Mouthwash Compounding Diphenhydramine hydrochloride (0.525 g/0.525g) + Hydrocortisone (0.06 g/0.06g) + Nystatin (0.6 g/0.6g) Kit Oral CutisPharma, Inc. 2010-12-15 Not applicable US - International/Other Brands
- Aleryl / Alledryl / Allerdryl (Valeant) / Baramine / Beldin / Belix / Benylan (Biogen) / Dermodrin (Montavit) / Desentol (Meda) / Dibondrin (Montavit) / Dimedrol (Zdorovie) / Diphen (Wockhardt) / Dormarex 2 / Genahist / Histaxin (Meda) / Hyrexin (Hyrex) / Nytol Quickgels (GlaxoSmithKline) / Restamin (Kowa Souyaku) / Siladryl / Silphen Cough
- Categories
- Amines
- Aminoalkyl Ethers
- Anesthetics
- Anesthetics, Local
- Anti-Allergic Agents
- Anticholinergic Agents
- Antiemetics
- Antihistamines for Systemic Use
- Antihistamines for Topical Use
- Antipruritics, Incl. Antihistamines, Anesthetics, Etc.
- Autonomic Agents
- Benzene Derivatives
- Benzhydryl Compounds
- Central Nervous System Agents
- Central Nervous System Depressants
- Cytochrome P-450 CYP2C9 Substrates
- Cytochrome P-450 CYP2D6 Inhibitors
- Cytochrome P-450 CYP2D6 Inhibitors (moderate)
- Cytochrome P-450 CYP2D6 Substrates
- Cytochrome P-450 Enzyme Inhibitors
- Dermatologicals
- Ethanolamine Derivatives
- Ethylamines
- First Generation Antihistamines
- Gastrointestinal Agents
- Histamine Agents
- Histamine Antagonists
- Histamine H1 Antagonists
- Hypnotics and Sedatives
- Muscarinic Antagonists
- Neurotransmitter Agents
- OCT2 Inhibitors
- Peripheral Nervous System Agents
- Potential QTc-Prolonging Agents
- QTc Prolonging Agents
- Sensory System Agents
- Serotonergic Drugs Shown to Increase Risk of Serotonin Syndrome
- Sleep Aids, Pharmaceutical
- UNII
- 8GTS82S83M
- CAS number
- 58-73-1
- Weight
- Average: 255.3547
Monoisotopic: 255.162314299 - Chemical Formula
- C17H21NO
- InChI Key
- ZZVUWRFHKOJYTH-UHFFFAOYSA-N
- InChI
- InChI=1S/C17H21NO/c1-18(2)13-14-19-17(15-9-5-3-6-10-15)16-11-7-4-8-12-16/h3-12,17H,13-14H2,1-2H3
- IUPAC Name
- [2-(diphenylmethoxy)ethyl]dimethylamine
- SMILES
- CN(C)CCOC(C1=CC=CC=C1)C1=CC=CC=C1
Pharmacology
- Indication
For the treatment of symptoms associated with Vertigo/Meniere's disease, nausea and vomiting, motion sickness and insect bite.
- Associated Conditions
- Pharmacodynamics
Diphenhydramine is an antihistamine of the ethanolamine class. Ethanolamine antihistamines have significant antimuscarinic activity and produce marked sedation in most patients. In addition to the usual allergic symptoms, the drug also treats irritant cough and nausea, vomiting, and vertigo associated with motion sickness. It also is used commonly to treat drug-induced extrapyramidal symptoms as well as to treat mild cases of Parkinson's disease. Rather than preventing the release of histamine, as do cromolyn and nedocromil, diphenhydramine competes with free histamine for binding at HA-receptor sites. Diphenhydramine competitively antagonizes the effects of histamine on HA-receptors in the GI tract, uterus, large blood vessels, and bronchial muscle. Ethanolamine derivatives have greater anticholinergic activity than do other antihistamines, which probably accounts for the antidyskinetic action of diphenhydramine. This anticholinergic action appears to be due to a central antimuscarinic effect, which also may be responsible for its antiemetic effects, although the exact mechanism is unknown.
- Mechanism of action
Diphenhydramine competes with free histamine for binding at HA-receptor sites. This antagonizes the effects of histamine on HA-receptors, leading to a reduction of the negative symptoms brought on by histamine HA-receptor binding.
Target Actions Organism AHistamine H1 receptor antagonistHuman UMuscarinic acetylcholine receptor M2 antagonistHuman - Absorption
Quickly absorbed with maximum activity occurring in approximately one hour.
- Volume of distribution
- Not Available
- Protein binding
98 to 99%
- Metabolism
Hepatic and renal
- Route of elimination
Little, if any, is excreted unchanged in the urine; most appears as the degradation products of metabolic transformation in the liver, which are almost completely excreted within 24 hours.
- Half life
1-4 hours
- Clearance
- Not Available
- Toxicity
LD50=500 mg/kg (orally in rats). Considerable overdosage can lead to myocardial infarction (heart attack), serious ventricular dysrhythmias, coma and death.
- Affected organisms
- Humans and other mammals
- Pathways
Pathway Category Diphenhydramine H1-Antihistamine Action Drug action - Pharmacogenomic Effects/ADRs
- Not Available
Interactions
- Drug Interactions
Drug Interaction (2-benzhydryloxyethyl)diethyl-methylammonium iodide The risk or severity of adverse effects can be increased when Diphenhydramine is combined with (2-benzhydryloxyethyl)diethyl-methylammonium iodide. 1,10-Phenanthroline The therapeutic efficacy of Diphenhydramine can be decreased when used in combination with 1,10-Phenanthroline. 2,5-Dimethoxy-4-ethylamphetamine The risk or severity of serotonin syndrome can be increased when Diphenhydramine is combined with 2,5-Dimethoxy-4-ethylamphetamine. 2,5-Dimethoxy-4-ethylthioamphetamine The risk or severity of serotonin syndrome can be increased when Diphenhydramine is combined with 2,5-Dimethoxy-4-ethylthioamphetamine. 3,4-Methylenedioxyamphetamine The risk or severity of serotonin syndrome can be increased when Diphenhydramine is combined with 3,4-Methylenedioxyamphetamine. 4-Bromo-2,5-dimethoxyamphetamine The risk or severity of serotonin syndrome can be increased when Diphenhydramine is combined with 4-Bromo-2,5-dimethoxyamphetamine. 4-Methoxyamphetamine The metabolism of 4-Methoxyamphetamine can be decreased when combined with Diphenhydramine. 5-methoxy-N,N-dimethyltryptamine The risk or severity of serotonin syndrome can be increased when Diphenhydramine is combined with 5-methoxy-N,N-dimethyltryptamine. 7-Nitroindazole The risk or severity of adverse effects can be increased when Diphenhydramine is combined with 7-Nitroindazole. 7,8-Dichloro-1,2,3,4-tetrahydroisoquinoline The risk or severity of serotonin syndrome can be increased when Diphenhydramine is combined with 7,8-Dichloro-1,2,3,4-tetrahydroisoquinoline. - Food Interactions
- Avoid alcohol.
- Take with food.
References
- Synthesis Reference
Alison B. Lukacsko, Joseph J. Piala, "Effect of a combination of a terbutaline, diphenhydramine and ranitidine composition on gastrointestinal injury produced by nonsteroidal anti-inflammatory compositions." U.S. Patent US5260333, issued December, 1983.
US5260333- General References
- Raphael GD, Angello JT, Wu MM, Druce HM: Efficacy of diphenhydramine vs desloratadine and placebo in patients with moderate-to-severe seasonal allergic rhinitis. Ann Allergy Asthma Immunol. 2006 Apr;96(4):606-14. [PubMed:16680933]
- Abdi A, Rose E, Levine M: Diphenhydramine overdose with intraventricular conduction delay treated with hypertonic sodium bicarbonate and i.v. lipid emulsion. West J Emerg Med. 2014 Nov;15(7):855-8. doi: 10.5811/westjem.2014.8.23407. Epub 2014 Sep 19. [PubMed:25493135]
- Halpert AG, Olmstead MC, Beninger RJ: Mechanisms and abuse liability of the anti-histamine dimenhydrinate. Neurosci Biobehav Rev. 2002 Jan;26(1):61-7. [PubMed:11835984]
- Jaju BP, Wang SC: Effects of diphenhydramine and dimenhydrinate on vestibular neuronal activity of cat: a search for the locus of their antimotion sickness action. J Pharmacol Exp Ther. 1971 Mar;176(3):718-24. [PubMed:4329456]
- External Links
- Human Metabolome Database
- HMDB0001927
- KEGG Drug
- D00300
- KEGG Compound
- C06960
- PubChem Compound
- 3100
- PubChem Substance
- 46505484
- ChemSpider
- 2989
- BindingDB
- 50017674
- ChEBI
- 4636
- ChEMBL
- CHEMBL657
- Therapeutic Targets Database
- DAP000490
- PharmGKB
- PA449349
- IUPHAR
- 1224
- Guide to Pharmacology
- GtP Drug Page
- HET
- 2PM
- RxList
- RxList Drug Page
- Drugs.com
- Drugs.com Drug Page
- Wikipedia
- Diphenhydramine
- ATC Codes
- D04AA33 — Diphenhydramine methylbromide
- D04AA — Antihistamines for topical use
- D04A — ANTIPRURITICS, INCL. ANTIHISTAMINES, ANESTHETICS, ETC.
- D04 — ANTIPRURITICS, INCL. ANTIHISTAMINES, ANESTHETICS, ETC.
- D — DERMATOLOGICALS
- D04AA — Antihistamines for topical use
- D04A — ANTIPRURITICS, INCL. ANTIHISTAMINES, ANESTHETICS, ETC.
- D04 — ANTIPRURITICS, INCL. ANTIHISTAMINES, ANESTHETICS, ETC.
- D — DERMATOLOGICALS
- R06AA — Aminoalkyl ethers
- R06A — ANTIHISTAMINES FOR SYSTEMIC USE
- R06 — ANTIHISTAMINES FOR SYSTEMIC USE
- R — RESPIRATORY SYSTEM
- AHFS Codes
- 04:04.04 — Ethanolamine Derivatives
- 04:04.00 — First Generation Antihistamines
- PDB Entries
- 2aot
- MSDS
- Download (73.5 KB)
Clinical Trials
- Clinical Trials
Pharmacoeconomics
- Manufacturers
- Not Available
- Packagers
- Advance Pharmaceutical
- Advent Pharmaceuticals Inc.
- Amend
- APP Pharmaceuticals
- A-S Medication Solutions LLC
- Auriga Pharmaceuticals LLC
- Barr Pharmaceuticals
- Baxter International Inc.
- Bergen Brunswig
- Bioniche Pharma
- Bryant Ranch Prepack
- C.O. Truxton Inc.
- Cardinal Health
- Carlisle Laboratories Inc.
- Chattem Chemicals Inc.
- Concord Labs
- Consolidated Midland Corp.
- Contract Pharm
- CVS Pharmacy
- Darby Dental Supply Co. Inc.
- Dept Health Central Pharmacy
- Direct Dispensing Inc.
- DispenseXpress Inc.
- Dispensing Solutions
- Diversified Healthcare Services Inc.
- Eon Labs
- Equaline Vitamins
- Fusion Pharmaceuticals LLC
- General Injectables and Vaccines Inc.
- GlaxoSmithKline Inc.
- Goldline Laboratories Inc.
- Group Health Cooperative
- Hawthorn Pharmaceuticals
- Heartland Repack Services LLC
- Hospira Inc.
- Innoviant Pharmacy Inc.
- Ivax Pharmaceuticals
- Kraft Pharmaceutical Co. Inc.
- Liberty Pharmaceuticals
- Lnk International Inc.
- Major Pharmaceuticals
- Martin Surgical Supply
- McNeil Laboratories
- Medique Products
- Medtech Labs
- Merit Pharmaceuticals
- Midlothian Labs
- Mississippi State Dept Health
- Murfreesboro Pharmaceutical Nursing Supply
- Nexgen Pharma Inc.
- North Safety Products
- Nucare Pharmaceuticals Inc.
- Patient First Corp.
- PCA LLC
- PD-Rx Pharmaceuticals Inc.
- Perrigo Co.
- Pfizer Inc.
- Pharmaceutical Association
- Pharmedix
- Physicians Total Care Inc.
- Poly Pharmaceuticals Inc.
- Preferred Pharmaceuticals Inc.
- Prepackage Specialists
- Prepak Systems Inc.
- Prescript Pharmaceuticals
- Procter & Gamble
- Provident Pharmaceuticals LLC
- Remedy Repack
- Rite Aid Corp.
- River's Edge Pharmaceuticals
- Rugby Laboratories
- Sandhills Packaging Inc.
- Scientific Laboratories Inc.
- Silarx Pharmaceuticals
- Southwood Pharmaceuticals
- St Mary's Medical Park Pharmacy
- Tya Pharmaceuticals
- UDL Laboratories
- United Research Laboratories Inc.
- Vangard Labs Inc.
- Walgreen Co.
- Dosage forms
Form Route Strength Kit Topical Capsule; kit Oral Capsule Oral Cream Topical 20 mg/1mL Cream Topical 2.0 mL/100mL Liquid Oral 12.5 mg/5mL Capsule, gelatin coated Oral Powder Oral 25 mg/1 Cream Topical Liquid Oral 12.5 mg Solution Oral 12.5 mg Gel Topical 2 g/100g Cream Topical 2.0 % Patch Topical Injection, solution Intramuscular; Intravenous 50 mg/1mL Tablet Oral 25 mg Strip Oral 25 mg/1 Tablet, chewable Oral 12.5 mg Liquid Topical Liquid Oral 6.25 mg Cream Topical 2 % Elixir Oral 12.5 mg Gel Topical 20 mg/1mL Tablet, chewable Oral 25 mg Gel Topical 2 % Spray Topical Tablet Oral 25 mg/250mg Strip Oral 25 mg Syrup Oral Lotion Topical Suspension Topical Liquid Oral Tablet, coated Oral 25 mg/ 11 Syrup Oral 6.25 mg Tablet Oral 19 mg Strip Oral 19 mg Suspension Oral Tablet Oral 12.5 mg/1 Tablet, chewable Oral 12.5 mg/1 Kit; tablet Oral Ointment Topical Powder, for solution Oral Gel Topical Kit Oral 0.75 g/0.75g Kit Oral 0.86 g/0.86g Tablet Oral 38.0 mg Capsule, coated Oral 25 mg/1 Injection, solution Intravenous 50 mg/1mL Capsule, liquid filled Oral 20 mg/1 Tablet Oral 50 mg/1 Liquid Intravenous 50 mg Capsule Oral 25 mg/1 Capsule Oral 50 mg/1 Capsule, liquid filled Oral 50 mg/1 Elixir Oral 25 mg/10mL Injection Intramuscular 50 mg/1mL Injection Intramuscular; Intravenous 50 mg/1mL Injection Parenteral 50 mg/1mL Solution Oral 25 mg/10mL Solution Oral 50 mg/20mL Tablet, coated Oral 25 mg/1 Tablet, film coated Oral 25 mg/1 Liquid Intramuscular; Intravenous 50 mg Tablet, chewable Oral Kit Oral; Topical Capsule, liquid filled Oral Capsule, liquid filled Oral 25 mg/1 Solution Oral 50 mg/40mL Kit Oral Aerosol, spray Topical Liquid Topical 20.3 g/1L Spray Topical 2 g/100mL Gel Topical 2.03 g/100g Aerosol Topical Solution Topical Strip Oral 12.5 mg Tablet Oral 12.5 mg Tablet, orally disintegrating Oral 12.5 mg/1 Liniment Topical Capsule, gelatin coated Oral 50 mg/1 Kit Lozenge Oral 25 mg Strip Oral Solution Oral 50 mg/30mL Capsule Oral 25 mg Liquid Oral 50 mg/30mL Solution Oral 50 mg Tablet, film coated Oral 50 mg/1 Powder Oral Solution Oral Tablet Oral 50 mg Granule, for solution Oral Tablet, coated Oral Elixir Oral 2.5 mg Solution Oral 12.5 mg/5mL Syrup Oral 12.5 mg/5mL Gel Topical 20.5 mg/1mL Plaster Topical Solution Intramuscular; Intravenous 50 mg Gel Topical 2 g/100mL Gel Topical .2 g/10mL Tablet Oral Tablet, coated Oral 50 mg/1 Tablet, multilayer Oral Tablet, multilayer, extended release Oral Gel Topical 20 mg/1g Spray Topical 20 mg/1mL Capsule, coated Oral Tablet Oral 25 mg/1 Tablet, film coated Oral Capsule Oral 50 mg Tablet, chewable Oral 25 mg/1 Liquid Oral 6.25 mg/1mL Liquid Oral 25 mg/10mL Capsule, gelatin coated Oral 50 mg/21 Spray Topical 2.0 % Capsule, liquid filled Oral 50 mg/21 Liquid Oral 50 mg Capsule, gelatin coated Oral 25 mg/1 - Prices
Unit description Cost Unit DiphenhydrAMINE HCl 100 50 mg capsule Bottle 13.99USD bottle Diphenhydramine 50 mg/ml 3.94USD ml Diphenhydramine 50 mg/ml vial 1.69USD ml DiphenhydrAMINE HCl 50 mg/ml vial 1.44USD vial Dytan 25 mg tablet chewable 1.37USD tablet Benadryl 50 mg/ml vial 1.36USD ml Diphenmax 25 mg tablet 1.24USD tablet Benadryl allergy 25 mg strips 0.45USD strip Unisom sleep aid tablet 0.34USD tablet Sleep-eze 3 tablet 0.29USD tablet Compoz 50 mg tablet 0.27USD tablet Sominex max str 50 mg caplet 0.27USD caplet Benadryl allergy fastmelt tablet 0.26USD tablet Unisom 25 mg sleeptabs 0.25USD tablet Unisom 50 mg sleepgels 0.25USD each Unisom sleepmelts 25 mg tablet 0.24USD tablet Nytol 25 mg tablet 0.23USD tablet Benadryl allergy-sinus caplet 0.22USD caplet Compoz 25 mg gelcap 0.2USD capsule Benadryl allergy 25 mg softgel 0.19USD softgel capsule Benadryl allergy 25 mg ultratab 0.19USD tablet Benadryl allergy-cold kapgels 0.19USD each Benadryl allergy-sinus kapgels 0.19USD each Benadryl-d allergy-sinus ultratab 0.19USD tablet Diphenhydramine hcl powder 0.17USD g Eql allergy 25 mg tablet 0.17USD tablet Nighttime sleep aid 25 mg cplt 0.17USD caplet Banophen anti-itch 2% cream 0.16USD g Benadryl itch relief stick 0.16USD ml Sominex 25 mg tablet 0.16USD tablet Benadryl allergy 25 mg kapgels 0.15USD each Allergy 25 mg tablet 0.14USD tablet Benadryl 25 mg kapseals 0.14USD each Benadryl itch stopping crm 0.14USD g DiphenhydrAMINE HCl 25 mg capsule 0.13USD capsule Diphenhist with zinc cream 0.12USD g Ra allergy 25 mg tablet 0.12USD tablet CVS Pharmacy allergy 25 mg tablet 0.11USD tablet Diphenhydramine 25 mg minitab 0.11USD tablet Simply sleep 25 mg caplet 0.11USD caplet Sleep ii tablet 0.11USD tablet Diphenhydramine 50 mg capsule 0.1USD capsule Benadryl 2% spray 0.09USD ml Diphenhist 50 mg tablet 0.09USD tablet Genahist 25 mg tablet 0.09USD tablet Ra sleep tablet 0.09USD tablet Banophen 25 mg tablet 0.08USD tablet Wal-dryl anti-itch spray 0.08USD ml CVS Pharmacy allergy 25 mg caplet 0.07USD caplet Nighttime sleep aid 25 mg caplet 0.07USD caplet CVS Pharmacy itch relief spray 0.06USD ml Diphen 25 mg capsule 0.06USD capsule Diphenhist 25 mg caplet 0.06USD caplet Benadryl anti-itch 0.45% gel 0.05USD g Diphenhydramine 50 mg caplet 0.05USD caplet Benadryl itch stopping gel 0.04USD g Child benadryl-d aller-sin liquid 0.04USD ml Diphenhydramine 25 mg capsule 0.04USD capsule Vicks 44d cough & head liquid 0.03USD ml Vicks 44e cough & chest liquid 0.03USD ml Banophen allergy liquid 0.02USD ml Diphenhydramine 25 mg tablet 0.02USD tablet Ra anti-tussive dm syrup 0.02USD ml Siladryl 12.5 mg/5 ml liquid 0.02USD ml Silphen cough syrup 0.02USD ml Silphen dm cough syrup 0.02USD ml DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only.- Patents
Patent Number Pediatric Extension Approved Expires (estimated) US8883849 No 2002-01-17 2022-01-17 US US9155718 No 2002-01-17 2022-01-17 US US8263647 No 2002-05-30 2022-05-30 US
Properties
- State
- Solid
- Experimental Properties
Property Value Source melting point (°C) 161-162 Martin, H., Hafliger, F.,Gatzi, K.and Grob, A.; U.S. Patent 2,397,799; April 2,1946; assigned to J.R. Geigy AG, Switzerland. Rieveschl, G. Jr.; U.S. Patent 2,421,714; June 3,1947; assigned to Parke, Davis & Co. Rieveschl, G. Jr.; U.S. Patent 2,427,878; September 23,1947; assigned to Parke, Davis & Company. boiling point (°C) 150-165 °C at 2.00E+00 mm Hg PhysProp water solubility 3060 mg/L (at 37 °C) BEILSTEIN logP 3.27 HANSCH,C ET AL. (1995) pKa 8.98 SANGSTER (1994) - Predicted Properties
Property Value Source Water Solubility 0.0752 mg/mL ALOGPS logP 3.44 ALOGPS logP 3.65 ChemAxon logS -3.5 ALOGPS pKa (Strongest Basic) 8.87 ChemAxon Physiological Charge 1 ChemAxon Hydrogen Acceptor Count 2 ChemAxon Hydrogen Donor Count 0 ChemAxon Polar Surface Area 12.47 Å2 ChemAxon Rotatable Bond Count 6 ChemAxon Refractivity 79.93 m3·mol-1 ChemAxon Polarizability 29.86 Å3 ChemAxon Number of Rings 2 ChemAxon Bioavailability 1 ChemAxon Rule of Five Yes ChemAxon Ghose Filter Yes ChemAxon Veber's Rule Yes ChemAxon MDDR-like Rule No ChemAxon - Predicted ADMET features
Property Value Probability Human Intestinal Absorption + 0.9898 Blood Brain Barrier + 0.9381 Caco-2 permeable + 0.8744 P-glycoprotein substrate Substrate 0.6211 P-glycoprotein inhibitor I Non-inhibitor 0.6632 P-glycoprotein inhibitor II Non-inhibitor 0.8381 Renal organic cation transporter Inhibitor 0.7752 CYP450 2C9 substrate Non-substrate 0.7897 CYP450 2D6 substrate Substrate 0.8919 CYP450 3A4 substrate Substrate 0.6173 CYP450 1A2 substrate Inhibitor 0.8306 CYP450 2C9 inhibitor Non-inhibitor 0.9144 CYP450 2D6 inhibitor Inhibitor 0.8932 CYP450 2C19 inhibitor Non-inhibitor 0.9039 CYP450 3A4 inhibitor Non-inhibitor 0.934 CYP450 inhibitory promiscuity Low CYP Inhibitory Promiscuity 0.7293 Ames test Non AMES toxic 0.9132 Carcinogenicity Non-carcinogens 0.6495 Biodegradation Not ready biodegradable 0.9253 Rat acute toxicity 2.7846 LD50, mol/kg Not applicable hERG inhibition (predictor I) Weak inhibitor 0.536 hERG inhibition (predictor II) Inhibitor 0.6318
Spectra
- Mass Spec (NIST)
- Not Available
- Spectra
Taxonomy
- Description
- This compound belongs to the class of organic compounds known as diphenylmethanes. These are compounds containing a diphenylmethane moiety, which consists of a methane wherein two hydrogen atoms are replaced by two phenyl groups.
- Kingdom
- Organic compounds
- Super Class
- Benzenoids
- Class
- Benzene and substituted derivatives
- Sub Class
- Diphenylmethanes
- Direct Parent
- Diphenylmethanes
- Alternative Parents
- Benzylethers / Trialkylamines / Dialkyl ethers / Organopnictogen compounds / Hydrocarbon derivatives
- Substituents
- Diphenylmethane / Benzylether / Tertiary aliphatic amine / Tertiary amine / Ether / Dialkyl ether / Organic nitrogen compound / Organic oxygen compound / Organopnictogen compound / Hydrocarbon derivative
- Molecular Framework
- Aromatic homomonocyclic compounds
- External Descriptors
- tertiary amino compound, ether (CHEBI:4636) / a small molecule (CPD-10890)
Targets
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Yes
- Actions
- Antagonist
- General Function
- Histamine receptor activity
- Specific Function
- In peripheral tissues, the H1 subclass of histamine receptors mediates the contraction of smooth muscles, increase in capillary permeability due to contraction of terminal venules, and catecholamin...
- Gene Name
- HRH1
- Uniprot ID
- P35367
- Uniprot Name
- Histamine H1 receptor
- Molecular Weight
- 55783.61 Da
References
- Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. [PubMed:11752352]
- Piao H, Nagai S, Tsurumaki T, Niki T, Higuchi H: Potentiation by neuropeptide Y of histamine H1 receptor-mediated contraction in rat blood vessels. Vascul Pharmacol. 2007 Apr;46(4):260-70. Epub 2006 Oct 27. [PubMed:17169617]
- Kesiova M, Alexandrova A, Yordanova N, Kirkova M, Todorov S: Effects of diphenhydramine and famotidine on lipid peroxidation and activities of antioxidant enzymes in different rat tissues. Pharmacol Rep. 2006 Mar-Apr;58(2):221-8. [PubMed:16702624]
- Hasala H, Moilanen E, Janka-Junttila M, Giembycz MA, Kankaanranta H: First-generation antihistamines diphenhydramine and chlorpheniramine reverse cytokine-afforded eosinophil survival by enhancing apoptosis. Allergy Asthma Proc. 2007 Jan-Feb;28(1):79-86. [PubMed:17390763]
- Wang Z, Woolverton WL: Self-administration of cocaine-antihistamine combinations: super-additive reinforcing effects. Eur J Pharmacol. 2007 Feb 28;557(2-3):159-60. Epub 2006 Dec 1. [PubMed:17196194]
- Ishikawa T, Takechi K, Rahman A, Ago J, Matsumoto N, Murakami A, Kamei C: Influences of histamine H1 receptor antagonists on maximal electroshock seizure in infant rats. Biol Pharm Bull. 2007 Mar;30(3):477-80. [PubMed:17329841]
- Havas TE, Cole P, Parker L, Oprysk D, Ayiomamitis A: The effects of combined H1 and H2 histamine antagonists on alterations in nasal airflow resistance induced by topical histamine provocation. J Allergy Clin Immunol. 1986 Nov;78(5 Pt 1):856-60. [PubMed:2878016]
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Unknown
- Actions
- Antagonist
- General Function
- G-protein coupled acetylcholine receptor activity
- Specific Function
- The muscarinic acetylcholine receptor mediates various cellular responses, including inhibition of adenylate cyclase, breakdown of phosphoinositides and modulation of potassium channels through the...
- Gene Name
- CHRM2
- Uniprot ID
- P08172
- Uniprot Name
- Muscarinic acetylcholine receptor M2
- Molecular Weight
- 51714.605 Da
References
- Liu H, Zheng Q, Farley JM: Antimuscarinic actions of antihistamines on the heart. J Biomed Sci. 2006 May;13(3):395-401. [PubMed:16453179]
Enzymes
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Unknown
- Actions
- SubstrateInhibitor
- General Function
- Steroid hydroxylase activity
- Specific Function
- Responsible for the metabolism of many drugs and environmental chemicals that it oxidizes. It is involved in the metabolism of drugs such as antiarrhythmics, adrenoceptor antagonists, and tricyclic...
- Gene Name
- CYP2D6
- Uniprot ID
- P10635
- Uniprot Name
- Cytochrome P450 2D6
- Molecular Weight
- 55768.94 Da
References
- Hamelin BA, Bouayad A, Drolet B, Gravel A, Turgeon J: In vitro characterization of cytochrome P450 2D6 inhibition by classic histamine H1 receptor antagonists. Drug Metab Dispos. 1998 Jun;26(6):536-9. [PubMed:9616188]
- Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014]
- Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256]
- Drug Interactions: Cytochrome P450 Drug Interaction Table [Link]
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Unknown
- Actions
- Substrate
- General Function
- Steroid hydroxylase activity
- Specific Function
- Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally un...
- Gene Name
- CYP2C9
- Uniprot ID
- P11712
- Uniprot Name
- Cytochrome P450 2C9
- Molecular Weight
- 55627.365 Da
References
- Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014]
- Connecticut's Official State Website: CYP Chart [File]
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Unknown
- Actions
- Substrate
- General Function
- Steroid hydroxylase activity
- Specific Function
- Responsible for the metabolism of a number of therapeutic agents such as the anticonvulsant drug S-mephenytoin, omeprazole, proguanil, certain barbiturates, diazepam, propranolol, citalopram and im...
- Gene Name
- CYP2C19
- Uniprot ID
- P33261
- Uniprot Name
- Cytochrome P450 2C19
- Molecular Weight
- 55930.545 Da
References
- Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014]
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Unknown
- Actions
- Substrate
- General Function
- Steroid hydroxylase activity
- Specific Function
- Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally un...
- Gene Name
- CYP2C18
- Uniprot ID
- P33260
- Uniprot Name
- Cytochrome P450 2C18
- Molecular Weight
- 55710.075 Da
References
- Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014]
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Unknown
- Actions
- Substrate
- General Function
- Prostaglandin-endoperoxide synthase activity
- Specific Function
- Converts arachidonate to prostaglandin H2 (PGH2), a committed step in prostanoid synthesis. Involved in the constitutive production of prostanoids in particular in the stomach and platelets. In gas...
- Gene Name
- PTGS1
- Uniprot ID
- P23219
- Uniprot Name
- Prostaglandin G/H synthase 1
- Molecular Weight
- 68685.82 Da
References
- Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014]
Transporters
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Unknown
- Actions
- Inhibitor
- General Function
- Quaternary ammonium group transmembrane transporter activity
- Specific Function
- Mediates tubular uptake of organic compounds from circulation. Mediates the influx of agmatine, dopamine, noradrenaline (norepinephrine), serotonin, choline, famotidine, ranitidine, histamin, creat...
- Gene Name
- SLC22A2
- Uniprot ID
- O15244
- Uniprot Name
- Solute carrier family 22 member 2
- Molecular Weight
- 62579.99 Da
References
- Urakami Y, Okuda M, Masuda S, Akazawa M, Saito H, Inui K: Distinct characteristics of organic cation transporters, OCT1 and OCT2, in the basolateral membrane of renal tubules. Pharm Res. 2001 Nov;18(11):1528-34. [PubMed:11758759]
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Unknown
- Actions
- Inhibitor
- General Function
- Secondary active organic cation transmembrane transporter activity
- Specific Function
- Translocates a broad array of organic cations with various structures and molecular weights including the model compounds 1-methyl-4-phenylpyridinium (MPP), tetraethylammonium (TEA), N-1-methylnico...
- Gene Name
- SLC22A1
- Uniprot ID
- O15245
- Uniprot Name
- Solute carrier family 22 member 1
- Molecular Weight
- 61153.345 Da
References
- Urakami Y, Okuda M, Masuda S, Akazawa M, Saito H, Inui K: Distinct characteristics of organic cation transporters, OCT1 and OCT2, in the basolateral membrane of renal tubules. Pharm Res. 2001 Nov;18(11):1528-34. [PubMed:11758759]
- Kind
- Protein
- Organism
- Human
- Pharmacological action
- Unknown
- Actions
- Inhibitor
- General Function
- Symporter activity
- Specific Function
- Sodium-ion dependent, high affinity carnitine transporter. Involved in the active cellular uptake of carnitine. Transports one sodium ion with one molecule of carnitine. Also transports organic cat...
- Gene Name
- SLC22A5
- Uniprot ID
- O76082
- Uniprot Name
- Solute carrier family 22 member 5
- Molecular Weight
- 62751.08 Da
References
- Ohashi R, Tamai I, Nezu Ji J, Nikaido H, Hashimoto N, Oku A, Sai Y, Shimane M, Tsuji A: Molecular and physiological evidence for multifunctionality of carnitine/organic cation transporter OCTN2. Mol Pharmacol. 2001 Feb;59(2):358-66. [PubMed:11160873]
Drug created on June 13, 2005 07:24 / Updated on October 21, 2018 20:29